The authors propose a fuzzy inference system (FIS) for the multistage partial parallel interference cancellation (PIC) multiuser detectors in a direct-sequence code-division multiple-access (DS-CDMA) communication system. The multistage PIC scheme is an effective method for the multiuser detection in the DS-CDMA systems, but the performance still suffers degradations in the near-far situations. Th...
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A tight bound for finite block-length codes is required when developing bandwidth efficient systems, and the paper describes an information-theoretic approach for determining the bound for binary codes. It is derived on the assumption that when the entropy loss in a binary symmetric channel equates to that in a soft-decision channel, the corresponding hard and soft-decision decoders must generate ...
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Outage analysis is one of the primary objectives in the design and operation of the current generations of cellular mobile communications systems, in order to increase spectrum efficiency and meet the quality of service and the grade of service demands. A general and unified semi-analytical approach is presented for the direct evaluation of the outage probability in the presence of L mutually inde...
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A serial concatenated convolutional and differential coding scheme is employed in a multi-user direct-sequence code-division multiple-access (DS-CDMA) system. The system consists of single-user detectors (SUDS), which are used to suppress multiple-access interference (MAI) with no requirement of other users' spreading codes, timing, or phase information. The differential code, treated as a convolu...
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Multimedia networks need sophisticated and real-time connection admission control (CAC) not only to guarantee the required quality of service (QoS) for existing calls but also to enhance utilisation of systems. The power spectral density (PSD) of the input process contains correlation and burstiness characteristics of input traffic and possesses the additive property. Neural networks have been wid...
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Binary sequences with ideal autocorrelation can be defined as the incidence functions for Hadamard difference sets. The authors consider a length of the form M=2m-1, m=nk, such that N=2n-1 and T=M/N are relatively prime. Width analyses show that a N×T generating array can be formed with shifted (and decimated) versions of subsequences of length N as its columns except f...
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One of the pertinent issues in IP router design is the IP routing table lookup. With high-speed multi-gigabit links required in the Internet, the lookup has become a great bottleneck. The authors propose a lookup scheme that can efficiently handle IP route lookup, insertion and deletion inside the routing table. This method is less complex in comparison to other schemes. By using careful memory ma...
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Generalised multiprotocol label switching (GMPLS) is being developed as a unified control architecture for the optical transport network and the layers above it. GMPLS supports traffic engineering (TE) by allowing explicit routing (ER) of data-bearing paths across networks, which will help to guarantee quality of service (QoS) for types of services in IP over WDM networks. Although there have been...
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A single-frequency wideband chirp sounder designed and implemented at UMIST was modified to carry out simultaneous measurements at the uplink and downlink frequencies of the UMTS bands. Measurements in the dense urban environment of Manchester city centre were carried out using both a trolley and a van, and power delay profiles were obtained over the two 60 MHz channels allocated for the frequency...
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Soft-decision differential phase detection (SD-DPD) with Viterbi decoding is proposed for the detection of trellis-coded FSK signals over a fading channel. The soft detector detects the differential phase and chooses a subregion among a preselected set of subregions at the end of every interval. The effect of the number of subregions is studied. The proposed system is analysed over a Rician channe...
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